Compact Lensless Fluorescence Counting System for Single Molecular Assay

In digital enzyme-linked immunosorbent assay, which is used for biomarker detection and diagnosis, the concentration of target biomarkers is estimated by counting the number of fluorescence chambers in the microchamber array. We propose a compact system for counting fluorescent chambers. Our system consists of three components: a micro-reaction chamber array, an absorption filter for attenuating excitation light, and a photodetector. The absorption filter has a micro-light-pipe array (m-LPA) structure. A stacked photodiode CMOS image sensor (CIS), which can discriminate color, is applied as a photodetector. This paper describes the fabrication process enabling thin m-LPA chips. The unique low-noise characteristics of the stacked photodiode CIS that attains high sensitivity by adopting the 4T-APS configuration are explained. Furthermore, a detection method using the photobleaching phenomenon is proposed for high-sensitivity fluorescence detection. This method suggests that fluorescence by a single molecular enzyme can be detected within 30 min of the start of the fluorescence reaction.

[1]  R. M. Guidash.  A 06μm CMOS Pinned Photodiode Color Imager Technology , 1997 .

[2]  R·B·默里尔.  Color separation in an active pixel cell imaging array using a triple-well structure , 1999 .

[3]  Takashi Tokuda,et al.  Dual-mode lensless imaging device for digital enzyme linked immunosorbent assay , 2014, Photonics West - Biomedical Optics.

[4]  Jun Ohta,et al.  High coupling efficiency contact imaging system having micro light pipe array for a digital enzyme-linked immunosorbent assay , 2015, 2015 IEEE Biomedical Circuits and Systems Conference (BioCAS).

[5]  Yuan Chen,et al.  A CMOS image sensor for monochromatic spectrum imaging , 2009, 2009 IEEE International Workshop on Imaging Systems and Techniques.

[6]  Jun Ohta,et al.  Complementary Metal-Oxide-Semiconductor Image Sensor with Microchamber Array for Fluorescent Bead Counting , 2012 .

[7]  Jun Ohta,et al.  Compact lensless digital counting system for fluorescent micro-reaction-chamber array , 2016, 2016 IEEE Biomedical Circuits and Systems Conference (BioCAS).

[8]  Jun Ohta,et al.  A CMOS image sensor with stacked photodiodes for lensless observation system of digital enzyme-linked immunosorbent assay , 2014 .

[9]  William H. Sawyer,et al.  Spectral properties of the prototropic forms of fluorescein in aqueous solution , 1996, Journal of Fluorescence.

[10]  Martin A. Green,et al.  Self-consistent optical parameters of intrinsic silicon at 300 K including temperature coefficients , 2008 .

[11]  F. Shapiro,et al.  A 0.6 /spl mu/m CMOS pinned photodiode color imager technology , 1997, International Electron Devices Meeting. IEDM Technical Digest.

[12]  Jun Ohta,et al.  Micro-light-pipe array with an excitation attenuation filter for lensless digital enzyme-linked immunosorbent assay , 2016 .

[13]  David R Walt,et al.  Digital concentration readout of single enzyme molecules using femtoliter arrays and Poisson statistics. , 2006, Nano letters.

[14]  Pamela Abshire,et al.  Optical filtering technologies for integrated fluorescence sensors. , 2007, Lab on a chip.

[15]  Hiroyuki Noji,et al.  A single-molecule enzymatic assay in a directly accessible femtoliter droplet array. , 2010, Lab on a chip.

[16]  Hiroyuki Noji,et al.  Large-scale femtoliter droplet array for digital counting of single biomolecules. , 2012, Lab on a chip.

[17]  Jonathan Ephraim David Hurwitz,et al.  A CMOS image sensor with a double-junction active pixel , 2003 .

[18]  David M. Rissin,et al.  Single-Molecule enzyme-linked immunosorbent assay detects serum proteins at subfemtomolar concentrations , 2010, Nature Biotechnology.

[19]  Rohan T Ranasinghe,et al.  Ultrarapid generation of femtoliter microfluidic droplets for single-molecule-counting immunoassays. , 2013, ACS nano.

[20]  Paul M. Hubel,et al.  Spatial frequency response of color image sensors: Bayer color filters and Foveon X3 , 2004, IS&T/SPIE Electronic Imaging.

[21]  Jane Ru Choi,et al.  Advances in digital polymerase chain reaction (dPCR) and its emerging biomedical applications. , 2017, Biosensors & bioelectronics.

[22]  Sang Keun Yoo,et al.  Real-time color imaging with a CMOS sensor having stacked photodiodes , 2004, SPIE Optics + Photonics.

[23]  T. Lee,et al.  An Active Pixel Sensor Fabricated Using CMOS / CCD Process Technology , 1995 .